多糖微生物絮凝剂对方解石与闪锌矿的絮凝作用及机理

Role and Mechanism of Polysaccharide-based Microbial Flocculant in Flocculation Calcite and Sphalerite

为改善混凝法沉降硫化铅锌矿浮选废水中固体悬浮物颗粒易形成二次污染等问题,以硫化铅锌尾矿中典型矿物闪锌矿与方解石为研究对象,考察了多糖型微生物絮凝剂(MBFP)对闪锌矿与方解石的絮凝性能,并对其作用机理进行了研究。结果表明:方解石在pH=7.0~9.0范围内与MBFP作用可形成较大絮体,絮凝率可达95%以上;闪锌矿颗粒在pH=6.0条件下形成的絮体尺寸和密实程度较pH=9.0时大;MBFP添加量对方解石与闪锌矿絮凝沉降效果有显著影响,用量过高方解石絮凝率不随MBFP用量增加而提高,闪锌矿絮凝率随MBFP用量增加而降低。Zeta电位、红外光谱分析表明,MBFP与方解石、闪锌矿表面的金属离子发生作用力较强的化学作用而吸附在矿物表面。

The flocculation performance of polysaccharide-type microbial bio-flocculant(MBFP)on the typical mineral sphalerite and calcite in lead-zinc sulfide tailings was investigated to solve the problem of secondary pollution caused by suspended solid particles in the flotation wastewater of lead-zinc sulfide ore by coagulation sedimentation,and the flocculation mechanism of micro fine sphalerite and calcite by MBFP was studied.The results show that both calcite and sphalerite can flocculate with MBFP.When calcite interacts with MBF in the range of pH=7.0~9.0,larger flocs can be formed and the flocculation rate is over 95%;the size and density of flocs formed by sphalerite particles at pH=6.0 are larger than those at pH=9.0.The amount of MBFP has a significant impact on the flocculation effect of calcite and sphalerite.When the MBFP dosage is too high,the flocculation rate of calcite does not increase with the MBFP dosage increases,the flocculation rate of sphalerite decreases rapidly with the MBFP dosage increases yet.Zeta potential and infrared spectrum analysis showed that MBFP adsorbed on the surface of minerals due to strong chemical interaction with metal ions on the surface of calcite and sphalerite.